Francis Lieber.

Library of universal knowledge. A reprint of the last (1880) Edinburgh and London edition of Chambers' encyclopaedia, with copious additions by American editors (Volume 13) online

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Online LibraryFrancis LieberLibrary of universal knowledge. A reprint of the last (1880) Edinburgh and London edition of Chambers' encyclopaedia, with copious additions by American editors (Volume 13) → online text (page 160 of 203)
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parties, and may be agreed upon at any stage of the suit, or even before any step baa
been taken in it.

SPECIAL JURY is a jury consisting of a superior class of men, such as esquires or
persons of higher degree, bankers, or merchants selected by the sheriff, and formed
into a separate, list. Either party to an action may demand a special jury, but he must
pay the extra expense, provided the judge do not certify at the conclusion of the trial
that it was a proper case to be tried by a special jury, in which case the costs are part
of the costs in the cause. Each special juryman gets a guinea for his attendance oa the
<;'.<('. The advantage of a special jury is, that the jurors are less likely to he carried away
with vulgar prejudices, and more intelligent, and able to understand difficult c

SPECIAL LICENSE, in the marriage law of England, means a license obtained from
the archbishop, which enables the priest to marry the parties without the publication of
bans, and also at anytime or place other than those necessary in ordinary cases. The
statute of 25 Henry V III. c. 21, entitled an act concerning Peter Pence and dispensations,
continued to the archbishop of Canterbury the same right as the pope previously had to
grant special licenses to marry at any convenient time and place. By a regulation of
archbishop (Seeker in 17o9, the privilege ia restricted to children of peers, and privy
councilors, judges, baronets, and knights. The same conditions apply to applicants as
in other cases, except that the special license merely authorizes a different time and place
for the marriage than in other cases. The stamp-duty is 5.

SPECIALTY DEBT, in English law. was a debt constituted by deed under seal, as a
bond, which in the event of the debtor's death had a right of prior payment over simple
contract (q.v.) debts. Such preference is, since 1870, abolished, except where a lieu or
other security is held for the debt.

SPE'CIES, in natural history, a term employed to designate groups inferior to genera
(see GKMJS), but superior to varieties (see VAKIETY). In mineralogy, the term is of very
arbitrary application, serving only, like class, order, genus, etc., the purpose of classifica-
tion, although it thus indicates common characters or points of real agreement among
minerals. In organic nature, it has usually been regarded as possessing a higher and
more definite signification. But no term is more difficult to define. Many definitions
have been proposed, but none wholly satisfactory; every attempt at definition involving
more or less the adoption of some disputed theory. If, for example, a species is regarded
as including all the beings which have descended from parents created with the essential
characters now belonging to the species, not only is the original creation in that particu-
lai^forrn taken for granted, but likewise the impossibility of changes in nature, which
gome of the most eminent naturalists regard' as actually taking plaee, and the belief of
which implies no doubt of the act of creation itself, but only a certain opinion as to some
of the laws by which organic nature is governed. To regard species as mere indeter-
minate and fluctuating groups, capable of indefinite modification in the lapse of ages, is
equally to adopt a theory. If a species is defined as containing all the individuals which.
are capable of intermingling without consequent sterility of progeny, other difficult
questions must be decided before the definition can be adopted as to any classes of crea-
tures, while to many kinds it seems incapable of application, and much that is merely the-
oretical is involved in it.

Naturalists have very generally regarded species as unchanging throughout the longest
succession of generations, except within narrow and marked limits, and have substan-
tially adopted the definition of Buffon: " A xpn-icx is a eon.-tant succession of individuals
similar to and capable of reproducing each other." Thus De Candolle, the eminent
botanist, says: "\Veuniteunderthe designation of a spfcicx all those individuals that
mutually bear to each other so close a resemblance as to allow of our supposing that they
m:iy have proceeded originally from a single being or a single pair." And Cuvier, the
great zoologist, describes a species as "a succession of individuals which reproduces and
perpetuates itself." Here it may be remarked, that even if the permanence of species
implied in these definitions were fully ascertained, and their original creation in their
present form admitted as unquestionable, it would by no means follow that we must sup-
pose; every species to have proceeded from a single individual or a single pair. Nor,
accepting' the Biblical statement concerning the human race, that all mankind are the
offspring of a single pair, are we entitled to infer that such has been the case also as to
all'animals and plants canable of freely intermingling, and which, therefore, are cotr.-
monly regarded as forming one specie.s.

But the separate creation and immutability of species are disputed, some naturalists
maintaining that species undergo modification, and that existing forms of life have
descended by true generation from pre-existing forms. Lamarck was the first to pro-
claim this doctrine, at least so as to attract much attention, about the beginning of the
19th century. He held that all species, even including man, are descended from species of
inferior organization; while to account for the existence of very simple forms at the
present day, he had recourse to the ^supposition of their spontaneous generation. He
was followed, with greater caution, by Geoffroy Saint-Hilaire, who regarded what
we call species as various degenerations of the same type, but did not believe that the
existing species are now undergoing modification. Similar views have since been stated


by many authors. But the works -which have most strongly direc- ^ attention to them,
and in which they have been most fully advocated, are the Vesfi;j - - _> ' 'lie Natural His-
tory of Creation, by an anonymous author, originally published in 1.^-44. and -which has
since passed through many editions; and Darwin's work On the u './in of Species by
means of Natural Selection' originally published in 1859. Of the other supporters of
these views, the most eminent is prof. Hnxley, who, without fully adopting the views
either of the author of the Vestiges or of Darwin, advocates " the hypothesis which sup-
poses the species living at any time to be the result of the gradual modification of pre-
existing species," and maintains that to suppose each species of plant and animal to h;;ve
been formed and placed on the surface of the globe at long intervals by a distinct act of
creative power, is an assumption "as unsupported by tradition or revelation as it is
opposed to the general analogy of nature."

It is impossible for us to do more than very briefly exhibit the principal arguments
which have been urged on this question. Lamarck rested much on the well-known effect
of use or exercise in strengthening and enlarging an organ, and of disuse in atrophying
it. "He conceived that, an animal being brought into new circumstances, and called
upon to accommodate itself to these, the exertions which it consequently made to that
effect caused the rise of new parts: on the contrary, when new circumstances left cer-
tain existing parts unused, these parts gradually ceased to exist. Something analogous
was, he thought, produced in vegetables, by changes in their nutrition, in their absorp-
tion and transpiration, and in the quantity of caloric, lignt, air, and moisture which
they received. This principle, with time, he deemed sufficient for the advance from the
monad to the mammal." .The author of the Vestiges from whom this account of Lamarck's
views is taken, regards him as in error " in giving this adaptive principle too much to
do;" and says: "In the present day, we have superior light from geology and physi-
ology, and hence comes the suggestion of a process analogous to ordinary gestation for
advancing organic life through its grades, in the course of a long but definite space of
time, with only a recourse to external conditions 'as a means of producing the exterior
characters." The author of the Vestiges designates the principle for which he contends
that of Progressive Development, and states it as follows: "The proposition determined
on, after much consideration, is, that the several series of animated beings, from the
simplest and oldest up to the highest and most recent, are, under tlie providence of God,
the results, .first, of an impulse which has been imparted to the forms of life, advancing
them in definite times, by generation, through grades of organization terminating in the
highost dicotyledons and vertebrata, these grades being few in number, and generally
marked by intervals of organic character which we find to be a praci ical difficulty ia ascer-
taining affinities; second, of another impulse connected with Uie vital forces, tending, m
the course of generations, to modify organic structures in accordance with external cir-
cumstances, as food, the nature of the habitat, and the meteoric agencies, these being
the 'adaptations' of the natural theologian." He further regards the undent-id ve*ic\', as
" the fundamental form of all organization, the meeting point between the inorganic
and the organic," and as " the starting point of the foetal progress of every higher indi-
vidual in creation, both animal and vegetable." Founding on instances of the produc-
tion of the proximate principles of which organic substances are composed in the labora-
tory of the chemist, he goes on to say that "an operation which would produce in the.-e
the nucleated vesicle is all that is wanting effectually to bridge over the space bot \veea
the inorganic and the organic;" and that " it does not seem, after all, a very immoderate
hypothesis, that a chemico-electric operation, by which germinal vesicles were produc&l. was
the first phenomenon in organic creation, and that the second was an advance of the*e
through a succession of higher grades, and a variety of inodifcati'ms in accordance with
laws of the same absolute nature as those by which the Almighty rules the physical
department of nature." He regards the idea of species or specific distinction, therefore,
"as merely applicable to certain appearances presented, perhaps transiently, to our notic".."
He adduces instances of great changes of form and character' known to take place in the
lower departments of nature, both animal and vegetable, as givi jg probability to the
supposition, that in a long succession of generations, great changes may take place also
in the higher.

The whole theory of the author of the Vestiges as to organic nnture has been exposed
to objection in consequence of its connection with views of the general system of the
universe altogether foreign to the present subject; and because of an evident inclination
to the belief in a transition from inorganic to organic existence by chemico-electric
operation. The argument is also weakened by the too ready acceptance of unsubstan-
tiated facts, as of the transmutation of one kind of grain into another; and by resting
too much on what may be reckoned the mere mistakes of naturalists, as to the forms
of the lower kinds of plants and animals, of which genera and even tribes have been
constituted, that have afterward been found to be mere modifications or larval stages of
creatures very different in their most apparent characters. Much hostility has been also
excited by the extension of the theory of development to the human species, connecting
man with pre-existing and inferior forms of animal existence. All this has been avoided
by Darwin, by whom, however, the chief arguments of the Vestiges are used with great
scientific caution.

Darwin's views are distinguished by the introduction of what he designates the prlu*


ciplo of natural selection. He maintains the variability of species, and adduces much
evidence to show that variation is continually taking place in consequence of the exter-
nal conditions to which plants and animals are subjected. He rests much on the diffi-
culty of distinguishing between varieties and species, and on the changes which are
known to result from cultivation and domestication. He dwells on the selection which
man makes in order to produce new breeds or varieties, and supposes a similar "selec-
tion" to take place in nature, in the struggle for life, which all "plants and animals must
undergo. This struggle for life is, in fact, the foundation of his theory. He shows that
every kind of plant or animal must maintain it, and in order to its continued existence,
mu>i be successful in maintaining it not only against those other creatures which seem
to make it their food, but still more in a competilion with those which seek the same
nutriment with itself. In this struggle the stronger, or those which possess anything
peculiarly favorable in their organization, must overcome the weaker, and these must
therefore cease to exist. Thus a slight variation, such as often takes place, may be per-
petuated; and the possessors of any advantage in the means of procuring food, or in the
powers of offense or defense, may entirely displace their less favored congeners. The
modifications thus taking place Darwin regards as accounting for the changes in organ-
ized beings from one geologic period to another, and for the great differences in the
plants and animals of different parts of the world. In support of his views, he argues
from the tendency to variation seen in cultivated plants and domestic animals, and the
perpetuation of the forms so produced in breeds and races; and from the fact that the
variations in cultivated and domestic species are in some cases greater than those which
are regarded as affording grounds of specific, and sometimes even of generic or greater
distinctions in a state of nature. "Can it be thought improbable," he says, "seeing
that variations useful to man have undoubtedly occurred, that other variations useful in
some way to each being in the great and complex battle of life, should sometimes occur
in the course of thousands of generations? If such do occur, can we doubt remember-
ing that many more individuals are born than can possibly survive that individuals
having any advantage, however slight, over others, would have the best chance of sur-
viving and of procreating their kind? On the other hand, we may feel sure that any
variation in the least degree injurious would be rigidly destroyed. This preservation of
favorable variations and the rejection of unfavorable variations, I call natural selection.
Variations neither useful nor injurious would not be affected by natural selection, and
would be left a fluctuating element, as perhaps we see in the species called polymorphic."
He further supports these views by pointing out the favorable opportunity for the oper-
ation of natural selection afforded in a country undergoing great physical changes, as of
climate; and particularly in an island, or a country surrounded by barriers sufficient to
prevent the ready immigration of species. "In such cases," he says, "every slight
modification, which in the course of ages chanced to arise, and which in any way
favored the individuals of any of the species by better adapting them to their altered
conditions, would tend to be preserved; and natural selection would thus have free scope
for the work of improvement."

Mr. Darwin supposes new variations to be continually taking place, but the greater
number of these speedily to become extinct; while others, becoming perpetuated, and
perhaps <-au>ing the extinction of the original forms, again give rise to other forms, until
some of them have so widely diverged that all traces of their common origin arc lost.
He does not, however, commit himself to the opinion that all forms of organic life, or
even all plants, or all animals, have a common origin. He completely rejects Lamarck's
notion that new and simple forms are continually being produced by spontaneous gen-
eration. "I need hardly say," he remarks, " that science in her present state does not
countenance the belief that living creature* are now ever produced from inorganic mat-
ter." and he accounts for the existence of low forms of life by saying that ''natural
se!i, ".ion includes no necessary and universal law of advancement or development: it
only takes advantage of such variations as arise and are beneficial to each creature under
its complex relations of life." So that even the lowest forms might " be left by natural
selection unimproved, or but little improved." as geology tells us of infusoria and rhizo-
pods which have remained for an enormous period in nearly their present state.

That species differ not only in single characters, but in many. Air. Darwin accounts
for by reference to unknown laws of ihe correlation of organs laws, however, which,
although unknown, we know to exist, so that a modification of one organ is attended
with modification of other organs, as is exemplified in our domestic breeds.

In further support of the theory of natural selection, the fact is insisted upon, "that
it is the common, the widely diffused, and widely ranging specie-, belonging to the
larger genera within each class, which vary most." That the several subordinate groups
in any class of creatures " cannot be ranked in a single file, but seem rather to be clus-
tered round points, and these round other points, and so on in almost endless cycles,"
Mr. Darwin thinks incapable of explanation, except on the supposition of community
of origin and natural selection. He points also to the analogous manner in which spe-
cies of the same genus vary, as corroborative of his views. He accounts for the absence
or rarity of transitional varieiies by supposing the predominant forms to have taken
possession of their districts, while these were in process of being stocked; and that these
districts, differing much in their natural characters, the forms originating in the com-


paratively unextcnsive intermediate tracts, have not been able to contend against them,
and have become extinct. He points out the possibility that areas now continuous may
not have been so during a long period, and that species may have been formed while
they wsre broken up into islands. But this remains a chief difficulty of his theory.

He ascribes'to natural selection the results which Lamarck ascribed to use and disuse
in the development and atrophy of organs; and thinks it not impossible that the flying
squirrels may thus have had a common origin with the true squirrels, and \\\c gnh'-p-i-
t/nf'i* with the lemurs, although he admits that we have no graduated links of struclura
connecting them together. ''Nor can I see any insuperable difficulty," he says, "in
1 i; tin r believing that the membrane-connected lingers and forearm of the raleopitfiecu*
might be greatly lengthened by natural selection; and this, as far as the organs of flight
are concerned, would convert it into a bat." Like Lamarck and the author of the Ves-
tiges, Mr. Darwin rests not a little on the unity of type throughout whole classes of
creatures, and the homologies of parts very different from each other, as in the four-
limbed structure of the vertebrata generally, and even the articulations of the limbs.
He endeavors to trace the eye from its simplest to its most perfect form, and shows how
gradual are the transitions found oii comparison of existing creatures, from the one to
the other. He goes even further, and says: " Several facts make me suspect that nerves
sensitive to touch may be rendered sensitive to light, and likewise to those coarser vibra-
tions of the air which produce sound."

He dwells at great length on the subject of hybridism, and the general sterility of
hybrids, endeavoring to show that it presents no insuperable objection to the theory of
a gradual modification of species, their sterility being incidental on other differences, and
sterility occurring, as he labors to prove, when varieties are crossed, as well as in the
hybrids of distinct species. The difficulties presented by geology he obviates very much
by insisting on the imperfection of the geological record. He does not adopt the view
of the author of the Vestiges, that the geological record exhibits to 113 a succession of
animals corresponding in their progressive development with the fetal development of
the mammalian embryo. But he founds an argument on the many connecting links in
the general system of nature which fossils supply when compared with existing sp-.cies.
And he endeavors to show that his theory is perfectly consistent with the Known facts
of the. geographical distribution of species, and in particular with the remarkable facts
of the peculiarity of the fauna and flora of some of the lonely oceanic islands, and of the
frequent occurrence of the same species both in cold regions comparatively rear the
j'ole. and on mountains far remote Irom each other in lower latitudes; referring the lat-
r class of facts 'to former geologic periods, when the continental areas were not the
.fan e as now, or when the prevailing climatic conditions were very different. Ami he
finds support for his views in the correspondence, without identity, of the floras and
faunas of the northern parts of America and of the Old World.

It is but a very imperfect sketch which we have thus been able to give of Darwin's
theory, and of the arguments by which it is supported Whatever may be thought of
the truth of the theory, it must be admitted to be admirably framed and guarded, and
to be maintained not 'only with great ingenuity of argument, but by the aid of a vast
store of scientific information, most skillfully used. Its opponents condemn it as resting
on unwarrantable assumptions, and demand some proof, for example, of the transition
of organs from a simple or rudimentary to a complex and more perfect state. They also
refuse to acknowledge such imperfection of the geological record as Darwin's argument
demands, and they insist much on the completeness of the changes which that record
discloses, and the absence of transitional forms both among fossils and existing species'.
jVIuch of what Darwin and other advocates of the same general views contend for, they
admit; a certain power of development in organic nature, a "struggle for life," and
" natural selection;" but they regard the limits of development and variation a? com-
paratively narrow. Nor would the state of the question, as they believe, be materially
affected, if many of what have hitherto generally been regarded as species, should be
proved to be mere varieties. Any number of such errors of naturalists might be exposed
and corrected, without modification of our views of the laws of nature; and errors of this
kind are precisely such as might be expected, when the forms of organic life began to be
discovered and described, and ere yet there was time for their mature study in all parts
cf the world, and under all various circumstances.

The doctrine of Darwin, or the Evolution Theory as it is usually named, continues t.
be a fruitful source of controversy. It has found many adherents in all countries, and
its leading principle " the survival of the fittest" lias been applied in other fields of
inquiry besides natural history. I;, ought to be mentioned that the eminent naturalist,
A. R. Wallace, unaware of the speculations Mr. Darwin was engaged it, had elaborated
independently a very similar scheme; and the prior publication of Darwin's labors was
chiefly accidental. The opponents of Darwinism are perhaps more numerous than its
adherents. The majority ground their arguments on the dangers they apprehend from
it ; they believe that its reception would sap the foundations of religion and social order.
But men of science bring against it a formidable' array of more legitimate arguments,
many of which it is found difficult to answer satisfactorily. Nevertheless the doctrine
seems to be working its way into general acceptance.



SPECIFIC GRAVITY of any body is the proportion which the -weight of a certain
biflk of that body bears to the same hulk of another body, which is taken as a standard.
The standard for sub-stances solid and liquid is distilled water at the temperature of 62
Fall., barometer 30 inches; and the weight of a cubic inch of this standard is given in
the Parliamentary Reports for 1S'25 as 2->2.4.j(J troy grains, hence a cubic foot of if weighs

Online LibraryFrancis LieberLibrary of universal knowledge. A reprint of the last (1880) Edinburgh and London edition of Chambers' encyclopaedia, with copious additions by American editors (Volume 13) → online text (page 160 of 203)